21528042 has 32 divisors (see below), whose sum is σ = 44029440. Its totient is φ = 7015920.

The previous prime is 21528037. The next prime is 21528071. The reversal of 21528042 is 24082512.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69067 + ... + 69377.

It is an arithmetic number, because the mean of its divisors is an integer number (1375920).

Almost surely, 2^21528042 is an apocalyptic number.

21528042 is an abundant number, since it is smaller than the sum of its proper divisors (22501398).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21528042 is a wasteful number, since it uses less digits than its factorization.

21528042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 538.

The product of its (nonzero) digits is 1280, while the sum is 24.

The square root of 21528042 is about 4639.8321090315. The cubic root of 21528042 is about 278.1857272100.

The spelling of 21528042 in words is "twenty-one million, five hundred twenty-eight thousand, forty-two".